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91.
台风防御是我国东南沿海各港口"三防"工作的重中之重。分析了目前我国港口防台工作的不足之处,提出了利用地理信息技术解决目前存在的问题,设计并开发了港口防台应急辅助决策与指挥系统。在软件整体架构设计、功能模块设计、数据设计等方面进行了研究,并介绍了"厦门港防台应急指挥系统"的应用情况。  相似文献   
92.
本文建立了夹套式外冷却燃气发生器燃烧室热防护的CFD数值模拟模型,并用该模型对影响热防护效果的各因素进行了研究。用有限容积法离散二维轴对称N-S方程,用标准k-ε模型模拟湍流,用可压缩耦合求解器求解控制方程。研究了燃烧室内壁材料热导率、燃烧室内壁壁厚以及冷却水流量对热防护效果的影响。结果表明材料热导率对热防护效果的影响较大,高热导率的材料能够明显降低燃烧室内壁壁温和温度梯度;当燃烧室内壁为高热导率材料时,壁厚和冷却水流量对热防护效果的影响相对较小。  相似文献   
93.
A constrained interpolation profile (CIP)-based Cartesian grid method for strongly nonlinear wave–body interaction problems is presented and validated by a newly designed experiment, which is performed in a two-dimensional wave channel. In the experiment, a floating body that has a rectangular section shape is used. A superstructure is installed on the deck and a small floating-body freeboard is adopted in order to easily obtain water-on-deck phenomena. A forced oscillation test in heave and a wave–body interaction test are carried out. The numerical simulation is performed by the CIP-based Cartesian grid method, which is described in this paper. The CIP scheme is applied in the Cartesian grid-based flow solver. New improvements of the method include an interface-capturing method that applies the tangent of hyperbola for interface capturing (THINC) scheme and a virtual particle method for the floating body. The efficiency of the THINC scheme is shown by a dam-breaking computation. Numerical simulations on the experimental problem for both the forced oscillation test and the wave–body interaction test are carried out, and the results are compared to the measurements. All of the comparisons are reasonably good. It is shown, based on the numerical examples, that the present CIP-based Cartesian grid method is an accurate and efficient method for predicting strongly nonlinear wave–body interactions.  相似文献   
94.
接触网参数测量系统可以实现接触网日常施工计算机管理,该系统利用计算机图像处理技术和lisp语言,将现场的实际状况与接触网专业技术有机地结合起来,改变了现有的测量方法,提高了现场作业效率.  相似文献   
95.
京福高速公路徐州绕城西段煤矿采空区处治研究   总被引:2,自引:0,他引:2  
京福高速公路徐州绕城西段穿越徐州市北部和西部,要通过富水倾斜的复杂煤矿采空区,经过采用注浆立填法进行处治取得了成功,可为今后类似复杂采空区处理的勘察设计和治理工程提供技术借鉴和指导作用。  相似文献   
96.
大跨度桥型方案比选。应在技术可行的前提下,对桥梁的经济性、美观性和创新性进行系统的分析、论证与比较,力争找到一个既能突出当地经济特色、人文思想及价值观念,又能表达现当代桥梁的技术水平及蕴涵未来桥梁的发展趋势的最佳方案。  相似文献   
97.
在公路客运枢纽方案评价过程中,涉及大量不确定因素和模糊因素。为协调这些因素,并降低人为因素的影响,采用二元对比重要性排序采确定各因素的权重,将备选方案与理想方案的几何偏差作为选优依据,为科学合理地的选择公路客运枢纽提供一种定量的方法,最后给出实例说明方法的实用性。  相似文献   
98.
张杰  罗宁 《水运工程》2017,(7):145-148
葛洲坝1号船闸由于与三峡船闸匹配运行,船舶实行导航墙待闸,下行船舶在导航墙停靠时距离人字门较近,而且下行船舶首船进闸后停靠位置与下闸首人字门距离较近,都具有碰撞人字门的风险。针对葛洲坝1号船闸人字门存在被碰撞的风险,结合上、下闸首的现场情况分别就上、下闸首人字门增设防撞设施方案的可能性进行分析,提出提升式、侧开式和下沉式等方案,并讨论各方案实现的可能性、优势及不足,为船闸人字门防撞安全设施的方案设计及应用提供参考。  相似文献   
99.
Travel to and from school can have social, economic, and environmental implications for students and their parents. Therefore, understanding school travel mode choice behavior is essential to find policy-oriented approaches to optimizing school travel mode share. Recent research suggests that psychological factors of parents play a significant role in school travel mode choice behavior and the Multiple Indicators and Multiple Causes (MIMIC) model has been used to test the effect of psychological constructs on mode choice behavior. However, little research has used a systematic framework of behavioral theory to organize these psychological factors and investigate their internal relationships. This paper proposes an extended theory of planned behavior (ETPB) to delve into the psychological factors caused by the effects of adults’ cognition and behavioral habits and explores the factors’ relationship paradigm. A theoretical framework of travel mode choice behavior for students in China is constructed. We established the MIMIC model that accommodates latent variables from ETPB. We found that not all the psychological latent variables have significant effects on school travel mode choice behavior, but habit can play an essential role. The results provide theoretical support for demand policies for school travel.  相似文献   
100.
This study identified a set of applicable and practical green performance evaluation indices for Chinese ports using the Delphi technique. The research was conducted by targeting three representative Chinese ports in Eastern China: the Shanghai Port, Ningbo Port, and Qingdao Port. An effective expert panel was structured with direct stakeholders related to green performance, which was based on a sufficient consideration of the unique and the special decision-making system for Chinese ports. Twenty-one green performance indices in six dimensions (i.e. liquid pollution management, air pollution management, noise control, low carbon regulations and energy savings, marine biology preservation, and organization and management) were eventually identified through three rounds of iterations. The identified green performance indices for Chinese ports are highly consistent with the Chinese Government’s environmental policies. Compared with European ports, the green port performance indicators in China are not as comprehensive. The indicators that are strictly consistent with national macro policies and the factors that are more easily seen, heard, and felt were perceived to be more important. From an academic perspective, this study offers a new approach for system establishment and green practice criteria exploration and thus provides a significant basis for further green port studies.  相似文献   
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